1. Field of the Invention
The present invention relates to a valve, and more particularly to a valve with an anti-loosening stem that is mounted firmly in a valve member. The valve prevents the anti-loosening stem from being jetted out of the valve member which damages users who remove a bonnet to replace fillers.
2. Description of the Related Art
A ball valve has a valve body, a spherical member and a stem. The stem is mounted through the valve body and mounted in the spherical member that is mounted inside a valve body and has a through hole defined through the spherical member. A user manipulates the stem to rotate the spherical member, and the spherical member controls fluid inside a pipe system to circulate or to close.
With regard to a conventional ball valve, for example, as disclosed in utility model patent No. TW311669, a stem is mounted in a spherical member and has an extending part that is formed at one of two ends of the stem. The spherical member has a recess that receives the extending part of the stem and is defined in a top end of the spherical member. To control a pipe system, a user manipulates the stem to rotate the spherical member.
A filler is mounted between the stem and the valve body to prevent fluid leakage along the stem because of high fluid pressure in the pipe system when the fluid passes through the ball valve. Furthermore, a bonnet is mounted around the stem and the filler to stick the valve body.
When fatigue occurs to the filler because of long term usage, the sealing capacity of the filler is decreased. Then, the user removes the bonnet and the stem to replace the filler. However, the connection between the stem and the spherical member is not firm. When the user removes the bonnet from the valve body, the stem may be inadvertently loosened, detached and even ejected from the spherical member damaging the user due to high fluid pressure inside the valve body.